Heparan sulfate regulates the fate decisions of human pluripotent stem cells

Deepsing Syangtan; Deena Al Mahbuba; Sayaka Masuko; Qiao Li; Andrew C Elton; Yefim Zaltsman; Paul J Wrighton; Ke Xia; Xiaorui Han; Yilan Ouyang; Fuming Zhang; Robert J Linhardt; Laura L Kiessling

doi:10.1016/j.stemcr.2024.11.014

Heparan sulfate regulates the fate decisions of human pluripotent stem cells

Stem Cell Reports. 2024 Dec 24:102384. doi: 10.1016/j.stemcr.2024.11.014. Online ahead of print.

Authors

Affiliations

¹ Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
² School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI 53705, USA.
³ Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA.
⁴ Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, 110 8th St., Troy, NY 12180, USA.
⁵ Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA; Broad Institute of MIT and Harvard, 415 Main St, Cambridge, MA 02142, USA; Koch Institute for Integrative Cancer Research at MIT, 500 Main St, Cambridge, MA 02142, USA. Electronic address: [email protected].

PMID: 39729990
DOI: 10.1016/j.stemcr.2024.11.014

Abstract

Heparan sulfate (HS) is an anionic polysaccharide generated by all animal cells, but our understanding of its roles in human pluripotent stem cell (hPSC) self-renewal and differentiation is limited. We derived HS-deficient hPSCs by disrupting the EXT1 glycosyltransferase. These EXT1^-/- hPSCs maintain self-renewal and pluripotency under standard culture conditions that contain high levels of basic fibroblast growth factor(bFGF), a requirement for sufficient bFGF signaling in the engineered cells. Intriguingly, Activin/Nodal signaling is also compromised in EXT1^-/- hPSCs, highlighting HS's previously unexplored involvement in this pathway. As a result, EXT1^-/- hPSCs fail to differentiate into mesoderm or endoderm lineages. Unexpectedly, HS is dispensable for early ectodermal differentiation of hPSCs but still critical in generating motor neurons. Those derived from HS-deficient hPSCs lack proper neuronal projections and show alterations in axonogenesis gene expression. Thus, our study uncovers expected and unexpected mechanistic roles of HS in hPSC fate decisions.

Keywords: CRISPR; EXT1; bFGF; basic fibroblast growth factor; ectoderm; glycan; glycosyltransferase; heparan sulfate; mesendoderm; neuron; nodal.